1. Field of the Invention
The present invention generally relates to printed circuit board apparatus and, in a preferred embodiment thereof, more particularly relates to apparatus for dissipating heat from a printed circuit board-mounted microprocessor.
2. Description of Related Art
As the internal die size and clock frequency of printed circuit board-mounted computer microprocessor chips continue to be increased the internal heat generated within the chips is correspondingly elevated. This, in turn, makes it increasingly important that the generated chip heat be efficiently dissipated to prevent the chip operating temperature from exceeding the manufacturer's prescribed limit and thereby causing improper functioning or failure of the chip.
Microprocessors are normally encased in a ceramic material which, as is well known, is a relatively poor conductor of heat. Accordingly, heat generated within the chip during its operation is difficult to remove through the insulation-like ceramic shroud within which the chip circuitry is encased. A conventional approach to dissipating the internal chip heat has been to mount cooling fins on the top or outer side of the ceramic outer chip body portion.
The use of top-mounted cooling fins on modern, higher speed microprocessor chips has not proven to be entirely successful in adequately removing internally generated heat from the chips due to the relatively low heat transfer coefficient of the ceramic material between the microprocessor's core silicon and the top-mounted cooling fins. Additionally, the use of these top mounted cooling fins tends to block from view the trademark, serial number and other important information typically stamped on the top side of the chip by its manufacturer.
From the foregoing it can be readily seen that it would be highly desirable to provide printed circuit board-mounted microprocessor chips, of the type generally described above, with improved heat dissipation apparatus. It is accordingly an object of the present invention to provide such improved microprocessor chip heat dissipation apparatus.